Ϊ358098 九、發明說明： 【發明所屬之技術領域】 本發明涉及一種換能器(transducer)，該換能器用於産生鍵合能量到感興 趣表面，例如超聲波導線鍵合過程中的電子器件的鍵合盤。 【先前技術】 在電子器件的生産過程中，有時需要在載體上裝配積體電路晶粒或晶 片。在安裝之後，通常通過使用鍵合導線，在晶片和載體之間形成電氣連 接。然後該産品被模塑成半導體封裝件。通過使用換能器的超聲波焊接， φ 這些鍵合導線分別被貼附到晶片和載體的鍵合盤上，該換能器以超聲波頻 率引起振動。 傳統的換能器包括：産生超聲波振動的壓電元件、超聲波放大角體 (amplifyinghorn)、通常以毛細尖管（capillary)或楔刀（wedge)形式存 在的鍵合工具。鍵合工具設置在放大角體的自由端，並一起被用於施加鍵 合力到被焊接的元件上。 放大角體通常被提供有凸緣或其他形式的安裝元件，通常當作爲管狀 體（barrel)或環管（collar)，其允許換能器被安裝到導線鍵合機器的鍵合 頭上，以在鍵合操作流程中根據需要在X、Y和Z軸上（以及在某些設計 中也圍繞旋轉或0軸軸線）移動。 • 當超聲波換能器被集成到導線鍵合機器中時，由於涉及到很精細的導 線和鍵合間距，所以超聲波換能器以何種方式被安裝到導線鍵合機器很重 要。例如，如果超聲波換能器是如此安裝以致於來自換能器的振動被傳遞 到安裝托架，那么産生了超聲波能量的損失。如果存在振動過大，那么換 , 能器的特性，如其頻譜特性可能改變，藉此影響了換能器的穩定性。而且， 換能器的阻抗可能不期望地發生改變，使得其更難以控制。因此，將超聲 波換能器如此安裝以致於超聲波鍵合期間産生的振動和換能器本身相隔 離，並盡可能地，將這些振動不傳送到導線鍵合機器的其他地方，是重要 的。 將換冑I器安裝到鍵合機器上的一種方法是通過引入凸緣（flange)。另 種方法是將換能器夾持到鍵合機器上。 5 1358098 在凸緣式安裝的超聲波換能器的情況中，對導線鍵合機器的振動能被 最小化的一種方式公開於一份美國專利中，其專利號爲“6，135,339”，發 明名稱爲“用於安裝在超聲波焊接設備，尤其是導線鍵合機上的帶凸緣的 超聲波換能器”。該專利啓示了 ：將凸緣安裝在角體縱向振動的節點上， 同時也形成具有足夠長度的凸緣以致於爲角體的徑向振動引入節點，從而 在所述的徑向節點處定位安裝點。這種超聲波換能器被安裝在這些徑向節 點位置，以便於在安裝點處的振動是盡可能最低的，並藉此減小對安裝有 換能器的導線鍵合機器的振動的傳遞。在角體相同的振動節點位置僅僅設 置有一對凸緣。 凸緣式安裝的超聲波換能器的另一個實例公開於又一份美國專利中， φ 其專利號爲“6,766,936”，發明名稱爲“換能器和使用該換能器的鍵合裝 置”。其描述了在放大角體的兩側設置有兩對凸緣支架，該凸緣支架包含 •有固定部、連接部，該固定部從和換能器主體的振動節點相應的不少於兩 個位置處凸伸，該連接部將凸伸的固定部的末端彼此連接。 在前述的專利中，固定部設置在換能器主體的相鄰的振動節點處，其 等同於振蕩波形的波長的一半。但是，前側固定部到換能器末端的距離大 於一個波長以外。問題是放大角體的懸挂部從前側固定部和換能器非常 長，懸挂部中導致較少的剛度。因此，通過使用更堅硬的材料或增力卩角體 的橫截面，角體的這個部位的剛度必須提高。否則，在鍵合時當換能器的 末端遭受負載時’換能器的懸挂部將會出現明顯的形變。 【發明内容】 本發明的目的在於尋求提供一種換能器’該換能器具有提高了的剛 度，以在鍵合期間降低換能器末端的形變，從而避免現有的換能器一些前 述的缺點。 ’ 因此，本發明提供一種換能器，該換能器包含有：角體，其被配置來 在操作過程中沿著其長度方向傳送振動，該振動是以包含有多個振動節點 的振蕩波形的形式；超聲波發生器，其和角體的一個端部相連；鍵合工具， 其和角體的相對的另一個端部相連以執行鍵合操作；第一凸緣結構，其沿 著角體的長度方向設置在第一振動節點處，以裝配該換能器；第二凸緣結 構，其沿著角體的長度方向設置在第二振動節點處’以裝配該換能器，該 Ϊ358098 第二凸緣結構和第一凸緣結構分隔一段距離，該距離爲至少兩個連續的振 動節點。 參閱後附的描述本發明實施例的附圖，隨後來詳細描述本發明是很方 便的。附圖和相關的描述不能理解成是對本發明的限制，本發明的特點限 定在申請專利範圍中。 【實施方式】 圖1是根據本發明較佳實施例所述的帶凸緣的換能器1 〇的立體示意 圖。該換能器10具有通常包含角體（hom) 12的延伸的主體。該角體12具有 尖端14，在該尖端處鍵合工具，如毛細尖管16可通過螺絲18安裝在角體12 • 上’以執行鍵合操作。包含有大量的壓電元件的超聲波發生器20在角體12 的相對的另一端處被安裝在角體12上。通常，超聲波發生器20以螺检的方 .式固定在角體12的端部。在操作中，角體12被配置來沿著其朝向毛細尖管 16的長度方向傳邊産生自超聲波發生器20的振動，以進行鍵合。通常，該 振動是以振蕩波形（oscillatory waveform)的形式傳送。 換能器10在沿著角體12長度方向上設置的第一凸緣結構22和第二凸緣 結構24的位置處被安裝在鍵合頭上（圖中未示）。第一凸緣結構22和第二凸 緣結構24中的每個具有從角體12上凸伸的頸部26、26’，在頸部處凸緣結構 被連接到角體12上。凸緣結構的安裝部可包括例如螺孔之類的安裝設備。 因此，螺孔28、28’可被形成在凸緣結構22、24上，以容納螺絲而將換能器 • 1〇安裝在鍵合頭上。在被闡述的本實施例中，第二凸緣結構24同樣也具有 位於包含螺孔28’的安裝部和頸部26’之間的延伸的肩部30，其大體平行於角 體12的縱軸延伸，以將螺孔28’和頸部26’連接。如果頸部26’（設置在角體 12上的振動節點位置）和鍵合頭上的安裝位置是不相符的，那么肩部30是 有用的，以允許螺孔28’被設置在鍵合頭上相應的安裝位置。 ' 圖2是帶凸緣的換能器10的平面示意圖，其表明當換能器10處於使用狀 態時，沿著換能器10的長度方向變化的振動幅度曲線。由超聲波發生器20 所産生的波形32具有振動幅度最小的多個振動節點位置（例如34、34’）。振 動幅度最大應該産生在換能器10的尖端I4，在執行導線鍵合的毛細尖管16 的位置處。 --第一凸緣結構22具有位於一個振動節點位置34處的、沿著角體丨2長度 I · ' 7 1358098 方向設置的頸部26，而第二凸緣結構24具有位於另一個振動節點位置34’處 的頸部26’。在節點34、34’處設置凸緣結構22、24防止超聲波能量被擴散到 鍵合頭。 . 在本發明較佳實施例中，第二凸緣結構24自第一凸緣結構22分隔一段 .距離，該距離爲沿著換能器10的角體12方向至少2個連續的節點，如圖2所 示。也就是說，在第一凸緣結構22和第二凸緣結構24之間（內）存在至少 —個未用的振動節點。更爲合適地，第一凸緣結構22和第二凸緣結構24被 安裝的兩個節點被分隔一個波長。 在現有的換能器中，在沿著換能器的角體方向上的兩個安裝點處，安 裝點被相互相鄰設置在連續的節點位置上，例如上述的專利號爲6,766,936 • 的美國專利（參見圖1)。通過將第一凸緣結構22和第二凸緣結構24分開一 段兩個或多個連續節點，更爲合適地爲一個波長的距離，由於安裝托架被 設置離尖端14更近，所以換能器10的剛度得以改良。這使得換能器1〇的尖 端14處的變形得以減小。 圖3是傳統的換能器100的側視示意圖，其表明當其遭受靜態負載時 的垂直方向上的位移。在這個範例中，靜態負載被向下施加，其等於〇.5kgb 傳統的換能器100具有角體102、用於安裝毛細尖管106進行鍵合的尖端 1〇4、安裝在角體102的相對端部的超聲波發生器108。傳統的換能器100 僅僅安裝在安裝管（mounting barrel) 110的位置，在該位置安裝管11〇被 夾持在鍵合頭上。換能器100在設置在安裝管110的振動節點位置處被夾 — 持。. 圖4是根據本發明較佳實施例所述的帶凸緣的換能器的側視示意圖，其 表明當其遭受靜態負載時的垂直方向上的位移，該靜態負載和圖3中所闡述 的施加子傳統的換能器的靜態負載同爲〇.5kgf。 • 表明傳統換能器1〇唾直方向位移的曲線36闡述了；傳統換能器1〇〇的 角體102基本上在安裝管11〇 (在此換能器1〇〇被夾持）和毛細尖管1〇6之間 沿著其長度方向出現了形變。另一方面，表明根據本發明較佳實施例所述 的帶凸緣的換能器10的角體I2在垂直方向的位移的曲線3欄述了 ：角體12 基本上在第二凸緣結構24和毛細尖管16之間沿著其長度方向出現了形變。 帶凸緣的換能器10的角體12被偏斜（deflected)的長度比傳統的換能器10〇 1358098 的角體102要短得多。結果，帶凸緣的換能器10所經受的偏斜量約爲2.〇Mm， 明顯低於傳統換能器1〇〇所經受的偏斜量’傳纖能器1〇嗎斜大約3.7职。 因此，在鍵合期間應用施加向下的力的方向上，帶凸緣的換能器10更加剛 性。 顯然，傳統的換能器安裝在安裝管Π0的位置，其距尖端104比第二凸 緣結構24距尖端Μ更加遠離。當角體I2容易受到偏斜的長度被縮短時，這 改善了帶凸緣的換能器10的剛性。因此，當毛細尖管16被壓入鍵合表面時， 帶凸緣的換能器10所遭遇到的偏斜小於傳統的換能器1 〇〇所遭遇的偏斜。 値得注意的是，在不需要增大角體12截面面積的情形下，本發明較佳 實施例所述的帶凸緣的換能器10可被製造得更爲剛性。因此，鍵合期間在 • 所施加的靜態負載的方向上，在加強剛度的同時’使得換能器的慣量最小 是可行的。 此處描述的本發明在所具體描述的內容基礎上很容易産生變化、修正 和/或補充，可以理解的是所有這些變化二修正和/或補充都包括在本發明的 上述描述的精神和範圍內。 ’Ϊ 358098 IX. Description of the Invention: [Technical Field] The present invention relates to a transducer for generating bonding energy to a surface of interest, such as a key of an electronic device during ultrasonic wire bonding Combined. [Prior Art] In the production process of electronic devices, it is sometimes necessary to mount integrated circuit dies or wafers on a carrier. After installation, an electrical connection is made between the wafer and the carrier, typically by using bond wires. The product is then molded into a semiconductor package. By ultrasonic welding using a transducer, φ these bonding wires are respectively attached to the bonding pads of the wafer and the carrier, which cause vibrations at an ultrasonic frequency. Conventional transducers include piezoelectric elements that generate ultrasonic vibrations, ultrasonic amplifying horns, and bonding tools that are typically present in the form of capillary or wedges. The bonding tool is placed at the free end of the enlarged angle body and is used together to apply a bonding force to the component being welded. The magnifying horn is typically provided with a flange or other form of mounting element, typically as a barrel or collar that allows the transducer to be mounted to the bond head of the wire bonding machine to The bonding operation moves in the X, Y, and Z axes (and in some designs around the rotation or 0 axis) as needed. • When the ultrasonic transducer is integrated into a wire bonding machine, it is important to install the ultrasonic transducer in the wire bonding machine because of the very fine wire and bonding pitch involved. For example, if the ultrasonic transducer is so mounted that vibration from the transducer is transmitted to the mounting bracket, a loss of ultrasonic energy is generated. If there is excessive vibration, then the characteristics of the transducer, such as its spectral characteristics, may change, thereby affecting the stability of the transducer. Moreover, the impedance of the transducer may change undesirably, making it more difficult to control. Therefore, it is important that the ultrasonic transducer is mounted such that the vibration generated during the ultrasonic bonding is isolated from the transducer itself and, as much as possible, the vibration is not transmitted to other places of the wire bonding machine. One way to mount the changer to the bonding machine is by introducing a flange. Another method is to clamp the transducer to the bonding machine. 5 1358098 In the case of a flange mounted ultrasonic transducer, one way of minimizing the vibrational energy of the wire bonding machine is disclosed in a U.S. patent, the patent number is "6,135,339", the name of the invention It is "a flanged ultrasonic transducer for mounting on ultrasonic welding equipment, especially wire bonders". This patent teaches that the flange is mounted on the longitudinally vibrating node of the horn, while also forming a flange of sufficient length to introduce a node for the radial vibration of the horn to position the installation at the radial node. point. Such ultrasonic transducers are mounted at these radial node locations to minimize vibration at the mounting point and thereby reduce the transmission of vibration to the wire bonding machine on which the transducer is mounted. Only a pair of flanges are provided at the same vibration node position of the horn. Another example of a flange mounted ultrasonic transducer is disclosed in yet another U.S. Patent, φ having the patent number "6,766,936" and entitled "Transducer and Bonding Device Using the Transducer". It describes that two pairs of flange brackets are disposed on both sides of the enlarged angle body, and the flange bracket includes a fixing portion and a connecting portion, and the fixing portion is not less than two corresponding to the vibration node of the transducer body. The position is convex, and the connecting portion connects the ends of the protruding fixing portions to each other. In the aforementioned patent, the fixing portion is provided at an adjacent vibration node of the transducer body, which is equivalent to half the wavelength of the oscillation waveform. However, the distance from the front side fixing portion to the end of the transducer is greater than one wavelength. The problem is that the suspension of the enlarged angle body is very long from the front side fixing portion and the transducer, resulting in less stiffness in the suspension portion. Therefore, the stiffness of this part of the horn must be increased by using a harder material or a cross section of the force horn. Otherwise, when the end of the transducer is subjected to a load during bonding, the suspension of the transducer will undergo significant deformation. SUMMARY OF THE INVENTION It is an object of the present invention to seek to provide a transducer that has an increased stiffness to reduce deformation of the transducer tip during bonding, thereby avoiding some of the aforementioned disadvantages of prior transducers. . Thus, the present invention provides a transducer comprising: a horn configured to transmit vibration along its length during operation, the vibration being an oscillating waveform comprising a plurality of vibration nodes Form; an ultrasonic generator connected to one end of the horn; a bonding tool connected to the opposite end of the horn to perform a bonding operation; a first flange structure along the horn a lengthwise direction disposed at the first vibration node to assemble the transducer; a second flange structure disposed along the length of the horn at the second vibration node to assemble the transducer, the Ϊ 358098 The two flange structures are separated from the first flange structure by a distance that is at least two consecutive vibration nodes. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in detail hereinafter with reference to the accompanying drawings in which: FIG. The drawings and the related description are not to be construed as limiting the invention, and the features of the invention are defined in the scope of the claims. [Embodiment] FIG. 1 is a perspective view of a flanged transducer 1 根据 according to a preferred embodiment of the present invention. The transducer 10 has an extended body that typically includes a horn 12 . The horn 12 has a tip end 14 at which a bonding tool, such as a capillary tip tube 16, can be mounted to the corner body 12 by screws 18 to perform a bonding operation. An ultrasonic generator 20 including a large number of piezoelectric elements is mounted on the horn 12 at the opposite end of the horn 12. Usually, the ultrasonic generator 20 is fixed to the end of the horn 12 by means of screwing. In operation, the horn 12 is configured to transmit vibrations from the ultrasonic generator 20 along its length toward the length of the capillary tip tube 16 for bonding. Typically, the vibration is transmitted in the form of an oscillatory waveform. The transducer 10 is mounted on the bonding head (not shown) at a position along the longitudinal direction of the corner body 12 at the first flange structure 22 and the second flange structure 24. Each of the first flange structure 22 and the second flange structure 24 has a neck portion 26, 26' projecting from the horn 12 at which the flange structure is attached to the horn 12. The mounting portion of the flange structure may include a mounting device such as a screw hole. Accordingly, the screw holes 28, 28' can be formed on the flange structures 22, 24 to accommodate the screws and the transducers 1 〇 on the bonding head. In the illustrated embodiment, the second flange structure 24 also has an extended shoulder 30 between the mounting portion including the threaded bore 28' and the neck portion 26' that is generally parallel to the longitudinal direction of the horn 12. The shaft extends to connect the screw hole 28' with the neck portion 26'. If the neck 26' (the position of the vibrating node disposed on the horn 12) does not match the mounting position on the bond head, the shoulder 30 is useful to allow the screw hole 28' to be placed on the bond head. Installation location. Figure 2 is a plan view of a flanged transducer 10 showing the amplitude of the vibration amplitude as a function of the length of the transducer 10 when the transducer 10 is in use. The waveform 32 produced by the ultrasonic generator 20 has a plurality of vibration node positions (e.g., 34, 34') having the smallest amplitude of vibration. The maximum amplitude of vibration should be generated at the tip end I4 of the transducer 10 at the position of the capillary tip tube 16 where the wire bonding is performed. - The first flange structure 22 has a neck 26 located at a vibration node location 34 along the length ·2 length I · ' 7 1358098, and the second flange structure 24 has another vibration node The neck 26' at position 34'. Flange structures 22, 24 are provided at nodes 34, 34' to prevent ultrasonic energy from being diffused to the bond head. In a preferred embodiment of the invention, the second flange structure 24 is separated from the first flange structure 22 by a distance which is at least 2 consecutive nodes along the direction of the horn 12 of the transducer 10, such as Figure 2 shows. That is, there is at least one unused vibration node between (inside) the first flange structure 22 and the second flange structure 24. More suitably, the two nodes to which the first flange structure 22 and the second flange structure 24 are mounted are separated by one wavelength. In prior transducers, at two mounting points along the angular direction of the transducer, the mounting points are placed adjacent to each other at successive node locations, such as the aforementioned US Patent No. 6,766,936 • Patent (see Figure 1). By separating the first flange structure 22 and the second flange structure 24 by a length of two or more consecutive nodes, more suitably a distance of one wavelength, since the mounting bracket is placed closer to the tip 14, the transducing The stiffness of the device 10 is improved. This allows the deformation at the tip end 14 of the transducer 1 to be reduced. Figure 3 is a side elevational view of a conventional transducer 100 showing the displacement in the vertical direction as it is subjected to a static load. In this example, the static load is applied downward, which is equal to 〇5 kgb. The conventional transducer 100 has a horn 102, a tip 1 〇 4 for mounting the capillary tip 106 for bonding, and a corner body 102. The opposite end of the ultrasonic generator 108. The conventional transducer 100 is mounted only in the position of a mounting barrel 110 where the mounting tube 11 is clamped to the bonding head. The transducer 100 is clamped at a position of a vibration node disposed at the mounting tube 110. Figure 4 is a side elevational view of a flanged transducer in accordance with a preferred embodiment of the present invention showing the vertical displacement as it is subjected to a static load, as illustrated in Figure 3 The static load of the conventional transducer is the same as 〇.5kgf. • A curve 36 indicating the displacement of the conventional transducer 1 〇 is explained; the horn of the conventional transducer 1 基本上 is substantially at the mounting tube 11 在 (where the transducer 1 〇〇 is clamped) and The capillary tip tube 1〇6 is deformed along its length. On the other hand, it is shown in the curve 3 of the displacement of the corner body I2 of the flanged transducer 10 according to the preferred embodiment of the present invention in the vertical direction: the angle body 12 is substantially in the second flange structure. The deformation between the 24 and the capillary tip 16 is along its length. The horn 12 of the flanged transducer 10 is deflected to a much shorter length than the horn 10 of the conventional transducer 10 〇 1358098. As a result, the amount of deflection experienced by the flanged transducer 10 is about 2. 〇Mm, which is significantly lower than the amount of deflection experienced by the conventional transducer 1 ' 'fiber-transistor 1 〇 obliquely 3.7 Job. Thus, the flanged transducer 10 is more rigid in the direction in which the downward force is applied during bonding. It will be apparent that conventional transducers are mounted at the location of the mounting tube ,0 which is further from the tip end 104 than the second flange structure 24 from the tip end. This improves the rigidity of the flanged transducer 10 when the length of the horn 1b is susceptible to deflection. Thus, when the capillary tip tube 16 is pressed into the bonding surface, the flanged transducer 10 encounters a deflection that is less than the deflection experienced by conventional transducers 1 。. It is noted that the flanged transducer 10 of the preferred embodiment of the present invention can be made more rigid without the need to increase the cross-sectional area of the horn 12. Therefore, it is feasible to minimize the inertia of the transducer while the stiffness is being tightened during the bonding in the direction of the applied static load. The invention described herein is susceptible to variations, modifications, and/or additions in addition to those specifically described. It is understood that all such variations and/or additions are included in the spirit and scope of the above described description of the invention. Inside. ’
9 1358098 【圖式簡單說明】 根據本發明所述的帶凸緣的換能器的較佳實施例的範例現將參考附圖 加以描述’其中： 圖1是根據本發明較佳實施例所述的帶凸緣的換能器的立體示意圖。 圖2是帶凸緣的換能器的平面示意圖，其表明沿著換能器的長度方向變 化的振動幅度曲線。 圖3是傳統的換能器的側視示意圖，其表明當其遭受靜態負載時的垂直 方向上的位移。 圖4是根據本發明較佳實施例所述的帶凸緣的換能器的側視示意圖，其 表明當其遭受靜態負載時的垂直方向上的位移，該靜態負載和圖3中所闡述 • 的施加于傳統的換能器的靜態負載相同。 【主要元件符號說明】 10換能器 12 角體 14 尖端 16 毛細尖管 18 螺絲 20 超聲波發生器 22 凸緣結構 • 24 第二凸緣結構 26 靡部 26’頸部 28 螺孔 28’螺孔 • 30肩部 32 波形 34 節點 34'節點 36 曲線 曲線 38 1358098 100換能器 102角體 104尖端. 106毛細尖管 108超聲波發生器 110安裝管9 1358098 [Simultaneous Description of the Drawings] An example of a preferred embodiment of a flanged transducer according to the present invention will now be described with reference to the accompanying drawings in which: FIG. 1 is in accordance with a preferred embodiment of the invention A perspective view of a flanged transducer. Figure 2 is a plan view of a flanged transducer showing a vibration amplitude profile that varies along the length of the transducer. Figure 3 is a side elevational view of a conventional transducer showing the displacement in the vertical direction as it is subjected to a static load. 4 is a side elevational view of a flanged transducer in accordance with a preferred embodiment of the present invention showing the vertical displacement as it is subjected to a static load, as illustrated in FIG. The static load applied to a conventional transducer is the same. [Main component symbol description] 10 transducer 12 horn 14 tip 16 capillary tip 18 screw 20 ultrasonic generator 22 flange structure • 24 second flange structure 26 26 26' neck 28 screw hole 28' screw hole • 30 shoulder 32 waveform 34 node 34' node 36 curve curve 38 1358098 100 transducer 102 corner body 104 tip. 106 capillary tip tube 108 ultrasonic generator 110 mounting tube